Hepatitis is one of the most harmful infectious diseases in the world, and is also related closely to the onset of liver cancer. According to statistical data from the World Health Organization (WHO), presently there are 350 million chronic hepatitis sufferers or asymptomatic patients infected by hepatitis viruses all over the world. All of these chronic hepatitis patients are at high risk of developing hepatocirrhosis and liver cancer. Over one million people die of diseases related to hepatitis, hepatocirrhosis and liver cancer each year. The incidence of hepatitis cases in China is high, and data shows that 90 percent of liver cancer patients were infected by the hepatitis viruses. Currently liver cancer is the second-most fatal tumor disease. To prevent and treat such a common, frequently occurring and refractory disease, researchers inside and outside of China have been focusing on and conducting clinical and pharmacological studies in liver protection and detoxification. Most countries treat chronic hepatitis B with a-interferon whose main effect is immunoregulation. Presently there are no specific drugs that can effectively treat hepatitis B and C caused by their respective viruses. The drugs against hepatitis B viruses are mostly the anti-HIV reverse transcriptase inhibitors and anti-herpes viruses DNA polymerase inhibitors. These two types of virus enzyme inhibitors are the target of anti-hepatitis B virus. The drugs used to fight hepatitis C viruses are mostly the broad-spectrum anti-virus drugs or RNA-virus inhibitors, and the immunoregulators having the activity of anti-viruses. However, the general problem with drugs currently available to use against hepatitis is that they are subject to drug-resistance.
Yan Huang Lian (Corydalis saxicola Bunting [Corydalis thalictrifolia Franch. Non Jameson ex Regel]), is a whole plant belonging to the family of papaveraceae. It is also known as Yan Hu (Guizhou), Yan Lian (Sichuan, Yunnan), Ju Hua Huang or Tu Huang Lian (Guangxi). Native residents in Guangxi use the roots of the plant as a pain killer, for detumescence, for drawing out pus and for treatment of scabies and swelling. Its current clinical application includes the use of its alkaloid extracts to treat hepatitis and hepatocirrhosis (Editorial Board of China Herbal. 1999. State Administration of Traditional Chinese Medicine. China Herbal, Vol. 3. Shanghai Science and Technology Press: Shanghai; 638-640).
In 1982, Chongyang Chen et al (Chen C Y, 1982. Pharmacological study of dehydrocavidine, the major constituent in Yan Huang-lian (Corydalis, saxicola Bunting). Trad Chin Med 7: 31-34.) investigated the pharmacological activity of dehydrocavidine which is the main constituent in Corydalis saxicola Bunting, and the results indicated that dehydrocavidine had sedative effects on the central nervous system; antispasm effects on the smooth muscles of the intestines; antibacterial effect in vitro; no effects on the blood sugar levels in normal mice; and effect on increasing the production of glycogen in vivo. In 1984, Qili Ye (Ye Q L. 1984. Anti-bacterial effect of dehydrocavidine from Corydalis saxicola. Gaungxi Zhongyiyao 3: 48-49.) investigated the anti-bacteria activity of dehydrocavidine in vitro, and the experiment proved that the dehydrocavidine had certain inhibitory effect on gram-positive bacterium. In 1996, Peishan Xie, et al. (Xie Peishan et al, “Screening tests of Chinese traditional medicines or herbal medicines in antitumor activity.” Shizhen Journal of Traditional Chinese Medicine Research, Vol. 7, no. 1, 1996, pages 19-20), reported that their anti-tumor experiment with this herb proved that the total alkali of Corydalis saxicola Bunting had a 30 percent inhibition rate on S180 carunclesarcoma at the dose of 1.6 mg/kg. In the past 10 years, some studies have indicated that the total alkali of Corydalis saxicola Bunting had an enhanced effect on the immune functions of mice, and certain inhibitory effects on the metabolism of DA and 5-HT in the rat's brain.
Yan Huang Lian (Corydalis saxicola Bunting) is clinically used as a supplementary therapeutic treatment of hepatitis. A study conducted by Zhongxuan Ren (Zhongxuan Ren, the efficacy analysis of 33 hepatitis cases treated with Yan Huang Lian (Corydalis saxicola Bunting), Clinical Focus, 18 (2): 94-95, 2003) showed that the injection of Yan Huang Lian (Corydalis saxicola Bunting Injecta) could effectively improve the clinical symptom of acute and chronic hepatitis. The Yan Huang Lian Injection combined with Shengmai injection have a distinct curative effect on hepatocirrhosis. Yan Huang Lian Injection combined with Danshen injection can effectively improve liver function, and relieve and inhibit liver fibrosis.
Although Corydalis saxicola Bunting has good clinical effects, the active constituents of this plant are still unclear and there are no practically feasible quality standards because of the lack of in-depth research on chemical constituents and the lack of sufficient screening of pharmacological activities.